John Wayne Gacy, was a serial killer who often worked as an amateur clown. He was convicted of murdering 33 young men and sentenced to death for 12 of these murders in March 1980. Gacy would often lure these men to his Chicago-area home for sex by impersonating a police officer or promising them construction work. He stabbed one and strangled the others between 1972 and 1978. Twenty-six bodies were buried in a crawl space under his home. Four other victims were dumped in a river. Gacy was executed in May, 1994.

Now, more than 30 years after these crimes, a collection of skeletal remains were found beneath Gacy's house. Detectives have secretly exhumed the bones of eight young men who were never identified in hopes of answering a final question: Who were they?

The Illinois Cook County Sheriff's Department says DNA testing could solve this mystery and identify some of these victims. Investigators are urging relatives of anyone who disappeared between 1970 and Gacy's 1978 arrest - and who is still unaccounted for - to undergo saliva tests to compare their DNA with that of the skeletal remains.